In pediatric medicine, almost every intervention is based on the weight of the patient. Medication doses are based on weight, resuscitation fluid volumes are based on weight, shock voltages administered during cardio-respiratory arrest are based on weight and breathing tubes are sized by weight. Yet, there are a number of circumstances where the weight of a child is unavailable. In developing countries, many medical clinics lack suitable scales that can be used to accurately obtain the weight of an infant or child. In developed countries, accurate estimates of a child's weight are rarely available during emergency/trauma situations both “in the field” and in the emergency room. In some settings, such as intensive care nurseries, scales are available but obtaining an accurate weight is impaired by the presence of external hoses, tubing and other medical equipment. Each of these scenarios pose a significant challenge to providing age-appropriate treatment including drug therapy with weight-based drug dosing which is recognized as the most accurate approach to delivering medicines.
Current strategies aimed at addressing weight estimation rely on; 1) age alone, 2) length alone, (e.g. total body length or height), or 3) age and length in some combination. Age based strategies fail to consider that two children of the same age may exhibit very different body compositions. Length based strategies do not take into consideration that two children of the same height may demonstrate markedly discrepant weights if one is malnourished/underweight or overweight/obese. Finally, age and length based strategies do not correct for the fact that weight increases disproportionately with height as children mature into adulthood. Importantly, all of the currently available weight estimation strategies perform well in only a small subset of children (i.e. those within normal limits of height and weight for age) deriving from the population in whom the method was developed.
What is needed in the art is an improved device and method for estimating the weight of a child or the appropriate dose of a medication that can easily be used in a clinical setting with greater accuracy than previous devices and methods. Further, what is needed is a method of making such a device based on creating a scale of numbers, indicia, or symbols that correspond to the weight of a child and/or dose of medication required, and/or degree of some other medical intervention.